1261346871408 has 160 divisors (see below), whose sum is σ = 3605019264000. Its totient is φ = 377507755008.

The previous prime is 1261346871401. The next prime is 1261346871427. The reversal of 1261346871408 is 8041786431621.

It is a Cunningham number, because it is equal to 1123097²-1.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261346871401) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 116796793 + ... + 116807591.

It is an arithmetic number, because the mean of its divisors is an integer number (22531370400).

Almost surely, 2^{1261346871408} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1261346871408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1802509632000).

1261346871408 is an abundant number, since it is smaller than the sum of its proper divisors (2343672392592).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1261346871408 is a wasteful number, since it uses less digits than its factorization.

1261346871408 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15919 (or 15913 counting only the distinct ones).

The product of its (nonzero) digits is 1548288, while the sum is 51.

The spelling of 1261346871408 in words is "one trillion, two hundred sixty-one billion, three hundred forty-six million, eight hundred seventy-one thousand, four hundred eight".